Conventionally, handy printers are known which are capable of printing desired information easily at a desired place.
In a printer of this type, for example, a printing tape cassette, which is provided with an ink ribbon and a printing tape, is removably set in the printer body. The ink ribbon and the printing tape are disposed in an overlapping manner between a print head and a platen roller in the printer body. In such a state, the platen roller presses the printing tape and the ink ribbon against the print head, and the platen roller is then rotated to feed the ink ribbon and the printing tape while the print head is being driven in accordance with print information to print desired information on the printing tape.
In this printer, the print head and the platen roller are disposed in an upstanding manner within the printer body so as to be closable with respect to each other. When the tape cassette is set within the printer body, the print head and the platen roller are moved away from each other, the ink ribbon and the printing tape are inserted from above in an overlapping manner in between the spaced print head and the platen roller. In printing, the platen roller approaches the print head to press the ink ribbon and the printing tape against the print head. The print head is attached to an upstanding protective member fixed at a lower end to a chassis attached within the printer body. The platen roller is attached rotatably at an upper and at a lower end to a support member which in turn is attached turnably to an upstanding support shaft, which is fixed at a lower end to the chassis. The support member is turned around the support shaft so as to move toward/away from the print head.
In such a printer, the protective member of the print head and the support shaft of the platen roller are fixed only at their lower ends to the chassis in an upstanding manner, but they are not fixed at their upper ends. Thus, by pressing the platen roller against the print head, the print head is likely to move away at its upper portion from the platen roller. Thus, the print head and the platen roller cannot be brought into uniform contact with each other through their lengths, so that there is a difference in printing state between the upper and the lower portions of the print head. As a result, uniform printing cannot be achieved and there is a deterioration in the print quality.
Such a problem would also arise in a structure in which the platen roller is fixed and in which the print head moves toward/away from the platen roller. In particular, when the respective lengths of the print head and the platen roller are increased to use a wider printing tape, the above described problem would be striking.